Get Package Info

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description adds substantial context beyond the annotations: it makes a live HTTP request, never returns cached/guessed/simulated data, returns explicit errors for missing packages or network failures, and provides verification fields. This complements the readOnly/idempotent hints without contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured with a clear purpose sentence, an Args block, a Returns line, and an Error Handling section. It is information-dense without redundancy, earning its length.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity and the rich schema/annotations, the description fully covers return fields and error behavior despite lacking an output schema. It tells the agent exactly what to expect, making it complete for safe invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Both parameters are fully described in the schema with 100% coverage, so the description's Args section mostly reiterates the schema. It adds example package names but no additional semantic constraints beyond what the schema already provides.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states it fetches real, current package metadata from npm, PyPI, or crates.io, with a specific verb and resource. It distinguishes itself from sibling tools by focusing on metadata retrieval rather than vulnerabilities, readmes, or search.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context for when to use the tool (when live, accurate metadata is needed) and emphasizes its live HTTP behavior. However, it does not explicitly compare against sibling tools or state when not to use it, so alternatives are not named.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.